Use keyczar backend module itself to detect if keyczar is supported for tests.
Fix NameError on Python 3 in tests
Add information about Travis-CI runner to the readme. Fixes #86.
Omit keyczar as well and link to the issue I just filed regarding the issue.
Explain how to launch the tests for Python 3

Fix #56
Include crypto even if keyczar isn't used

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extra : rebase_source : 717c36391a008325235677250e5d9792cc9ec386